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From: "unlvsur at live dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/107167] It looks like GCC wastes registers on
 trivial computations when result can be cached
Date: Thu, 06 Oct 2022 06:05:50 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107167

--- Comment #4 from cqwrteur <unlvsur at live dot com> ---
(In reply to Andrew Pinski from comment #1)
> Plus your example might be slower due to dependencies.


Dependency is only an issue to a certain degree. 1st one it has things like
"movl    %edi, %edx;  rorl    $11, %edx" which is also a flow dependency.

CPU solves flow dependency to a very large degree with register forwarding.

Write dependencies are also dealt with register renaming if we save registe=
rs,
register renaming will also save time.=